We propose four studies of disturbed gastric motility and transit after one or another type of ulcer surgery. Intestinal dilution indicator techniques, tracking of radioisotopically labeled food, and/or differential intraluminal manometry will be used to describe how solid and liquid foods move through the upper gastrointestinal tract. Specifically, we are interested in relations between rates of entry of food vs. rates of entry of digestive juices into the proximal intestine as well as the state of physical dispersion of solid food as it enters the upper intestine. Both of these functions ultimately affect digestion; and it is becoming increasingly apparent that most ulcer operations profoundly alter gastric emptying and dispersion of food. The aim of these and previous studies is finally to compare findings from each group of ulcer-operated subjects with those from normal subjects or from groups of subjects with other ulcer operations. Such comparisons may provide missing physiological information about these particular surgeries, some understanding of chronic morbidity each operation produces, and insight into human alimentary physiology and nutrition, particularly the digestive function of the human stomach.